六角形“趣题”的解
<br /="/"/><div>哈！又能上顶顶了<img /="/" src="/img/21.gif"></img>。色盲斑竹大概也是上不了顶顶吧，没见她发俺的证明（<a href="http://www.topchinesenews.com/readpost.aspx?topic_id=9&msg_id=8938&level_string=0z02&page=1&j_filter_url">http://www.topchinesenews.com/readpost.aspx?topic_id=9&msg_id=8938&level_string=0z02&page=1&j_filter_url</a>=），俺自己来发吧。（原题请见<a href="http://www.topchinesenews.com/readpost.aspx?topic_id=9&msg_id=8936&level_string=0&page=1&j_filter_url">http://www.topchinesenews.com/readpost.aspx?topic_id=9&msg_id=8936&level_string=0&page=1&j_filter_url</a>=）</div><div> </div><div><font style="BACKGROUND-COLOR: #ffff00">证明：设小菱形边长为1，正六边形边长为非负整数n。小菱形有三种，假设全覆盖时分别用x,y,z块。为保证正六边无缺口和内部无空隙，具平行边的菱形必须一对一地相接，从六边形的一边到对边，故有x+y=2n<sup>2</sup>。同样，y+z=2n<sup>2</sup>和z+x=2n<sup>2</sup>。解之，得x=y=z=n<sup>2</sup>。</font></div><div> </div><div>______________________________________________________________________________________________</div><div><br /="/"/>眼下脑坛有点冷清，坛友固有责，斑竹更有责。且饶一次斑竹，抛除成见、一起努力振兴脑坛吧。</div><span style="display:none;">www.ddhw.com</span><br /="/"/><br /="/"/> <div style="MARGIN-TOP:20px;MARGIN-LEFT:0;MARGIN-BOTTOM:0;float:left"></div>回复：六角形“趣题”的解
<table cellpadding="8" height="100%" width="100%"><tr><td valign="top"><br /="/"/><div>lili重出江湖了</div><span style="display:none;">www.ddhw.com</span><br /="/"/><br /="/"/> <div style="MARGIN-TOP:20px;MARGIN-LEFT:0;MARGIN-BOTTOM:0;float:left"></div></td></tr></table>
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